Apparatus for testing a nitrogen-gas-stabilized cement

Abstract

A testing apparatus is provided for measuring changes in the bulk volume and gas permeability of a cement slurry, such as one formed by dissolving in the slurry mix water a correlated amount of gas-forming reactants having a delayed rate of reaction such that the gas production occurs mainly at the time the volume of the slurry mix water is being reduced to a low value during the setting and hardening of the cement.

What is claimed is: 
     
       1. A cement slurry testing apparatus comprising: a test chamber having a substantially rigid-walled generally tubular portion;   means for flowing a sample of cement slurry into the chamber so that it fills at least a transverse section of said tubular portion;   means for inflowing and pressurizing a gas within the chamber so that a body of gas contacts and presses against said inflowed cement slurry;   means including a pump for maintaining the so-positioned gas and cement slurry within the chamber at a selected pressure and temperature; and,   means for measuring the amount of said pressurized gas which flows into or away from the transverse section of said chamber that was initially occupied by the cement slurry.   
     
     
       2. The apparatus of claim 1 in which said transverse section of the test chamber is located in a bottom portion of a generally U-shaped tube with upwardly extending legs.